When does nutrition during physical activity become important?

I need things to be kept as simply as possible. And I am not ashamed of it.

In my dealings with the world of nutrition this often becomes a problem for me. As Beth Mansfield, one of Canada’s leading sports dietitians, has been known to quip: “Nutrition is not rocket science… it’s much more complicated”. That’s why I’m relatively proud of myself (if I may say so) for coming up with the following table whose purpose is to answer the question as to whether or not a person needs to be concerned about nutrition during his/her physical activity.